SACRAMENTO, California - Scientists are assessing the damage from a massive wildfire burning around Yosemite National Park, laying plans to protect habitat and waterways as the fall rainy season approaches.

Members of the federal Burned Area Emergency Response team have been hiking the rugged Sierra Nevada terrain this weekend even as thousands of firefighters continue to battle the four-week-old blaze.

The 50 scientists are working to identify areas at the highest risk for erosion into waterways, including the reservoir that provides San Francisco with its famously pure water. Officials say they hope to have a report ready in two weeks so remediation can start before the first storms.

The wildfire started on Aug. 17 in the Stanislaus National Forest when a hunter's illegal fire swept out of control. It now ranks as the third-largest wildfire in modern California history, having burned 394 square miles of timber, meadows and sensitive wildlife habitat.